OAKLAND -- A wind advisory is in effect until early Monday in many Bay Area counties as strong gusts toppled power lines and trees, knocking out electricity to thousands of customers.

The National Weather Service issued the wind advisory for Alameda, Contra Costa, San Mateo, Napa, Marin and San Francisco counties, and reported that wind gusts were as strong as 51 mph in Oakland and San Francisco International Airport.

Downed power lines caused two outages in Vallejo, where about 5,500 customers lost power, according to PG&E. In Antioch, more than 3,200 customers were without power as of 9:30 p.m.

The Alameda County Fire Department posted a picture on Twitter of a building facade in the 5600 block of Bay Street in Emeryville that fell over due to strong winds.

In Pittsburg, authorities asked residents in the area of San Juan and Brookside drives to shelter in place due to downed power lines around 9:30 p.m.